Color photographic development utilizing pyrazolone couplers

ABSTRACT

In a color photographic developing process, the use of a coupler of the formula WHEREIN R is methyl or methoxy.

United States Patent Inventor Makoto Yoshida Kanagawa, Japan Appl. No.24,250 Filed Mar. 31, 1970 Patented Oct. 26, 1971 Assignee Fuji PhotoFilm Col, Ltd.

Nakanuma, Minami Ashigara-Machi, Ashigara-Kanigun, Kanagawa, JapanPriority Apr. 7, 1969 Japan 44/26266 COLOR PHOTOGRAPI-IIC DEVELOPMENTUTILIZING PYRAZOLONE COUPLERS 6 Claims, 2 Drawing Figs.

US. Cl 96/56.5, 260/3 10 Int. Cl G030 7/00 Field of Search 96/565, 100

Irimary Examine rJ. Travis Brown Attorney-Sughrue, Rothwell, Mion, Zinn& MacPeak ABSTRACT: In a color photographic developing process, the useof a coupler of the formula wherein R is methyl or methoxy.

PATENTEDHETHZB Ian 3, s 1 5.502

' FIG. I

OPTiCAL DENSITY 400 500 660 700 WAVE LENGTH (nm) WAVE LENGTH (nm)INVENTOR MAKOTO YOSHIDA BY 7411 444 ATTORNEYS COLOR PHOTOGRAPHICDEVELOPMENT UTILIZING PYRAZOLONE COUPLERS BACKGROUND OF THE INVENTION 1.Field of the Invention The present invention relates generally to colorphotography and more particularly to a color developer containing animproved coupler.

2. Description of the Prior Art .It is well kn'own.to use a coupler in acolor photographic development, whereby a color image is formed by thereaction of such coupler with the oxidation product of an aromaticprimary amine developing agent and many patents have been granted onsuch couplers, as well as on color photographic development processesusing such couplers. Such a coupler reacts with the oxidation product ofa developing agent to form a dye insoluble in an ordinary developingsolution,

whereby a color image is left in the photographic emulsion layer. Thereare two types of such couplers. The first is a coupler which isincorporated into a developer. The second is a coupler which isincorporated into a photographic emulsion layer prior to the exposure ofthe layer.

Such color development is generally performed by a subtractive colorprocess, and couplers that fonn cyan, magenta, and yellow dyes areemployed in the color development. Further it is necessary in colordevelopment processes, to employ couplers which form'dyes havingdesirable hues and transparencies.

Among such, the magenta-forming coupler is ideally required to form adye having such a color hue that it completely absorbs green light butis completely transparent to both blue and red light. Moreover, toimprove the transparency of the color image and to prevent the formationof a rough-appearing image, it is desirable that the granularity of thedye particles formed be fine and the granularity contrast be low. Thisis particularly important in order to improve the sharpness of theimage. It is further necessary that the dye formed be stable to heat,moisture, etc., and, in particular, it is most important that the dyepossess excellent stability in the presence of light.

As couplers satisfying the above factors, there are known suchderivatives as cyanoacetylcumarone, nitrophenylacetonitrile, indazolone,pyrazolone, and the like. Among them, it is well known thatl-phenyl-3-amino-5-pyrazolone derivatives having more than one halogenatom on the 1-phenyl group form a sharp'magenta dye possessing excellentcolor hue and also that such pyrazolone derivatives having anitroanilino group in the 3-position form a magenta dye having a highcolor density, as disclosed in British Patent No. 886,723, US. Pat. No.3,152,896, British Patent No. 956,261, and Belgian Patent No. 682,384,of appliant.

For example, British Patent No. 886,723, specifically discloses the useof l-(2,4,6-trichlorophenyl)-3-(4-nitroanilino)- 5-pyrazolone. US Pat.No. 3,152,896 relates to the use of l- (2,6-dichIoro-4-negativegroup-substituted phenyl)-3-anilino- S-pyrazolone. British Patent No.956,261 relates to the use of l-aryl-3(2-substitutedanilino)-5-pyrazolone. Furthermore, Belgian Patent No. 682,384 isconcerned with the use of l-(2,5-dichlorophenyl)-3-(4-nitroanilino)-5-pyrazolone.

However, the above-mentioned requirements are not sufficiently satisfiedeven by such couplers and hence it has been desired to discover improvedmagenta couplers for use in color development.

Thus, an object of the present invention is to provide a color developercontaining a magenta coupler which produces a dye having excellent lightfastness and excellent granularity.

Another object of the present invention is to provide'a color developercontaining an improved coupler capable of forming a magenta dye havingexcellent color hue and a' magenta image sufiiciently satisfying theaforesaid requirements.

A further object of the present invention is to provide an improvedmagenta coupler to be used in a color developer for providing a magentaimage sufficiently satisfying the aforesaid requirements.

SUMMARY OF THE INVENTION The above objects may be attained by using, assuch magenta coupler, a l-(2,6-dichloro-4-positive group-substitutedphenyl)-3-(4-nitroanilino)-5-pyrazolone, which compounds arecharacterized by possessing a positive methyl or methoxy group in the4-position of the l-phenyl nucleus and also possessing chlorine atoms inthe 2- and 6- positions thereof. This is to say, the magenta coupler ofthe instant invention is represented by the following general formula:

wherein R represents a member selected from the group consisting of amethyl group and a methoxy group.

These couplers of the present invention have excellentadvantages as willbe set forth below more fully.

BRIEF DESCRIPTION OF THE DRAWING In FIGS. 1 and 2 of the accompanyingdrawings are shown the comparison between the spectral absorption curvesE and F of color images formed by the coupling reaction of couplers Aand B of the present invention and the oxidation product of a colordeveloping agent, 2-methyl-4-N-ethyl-N-methanesulfoamino ethylaminoaniline, according to the process shown in example 1 and the spectralabsorption curves G and H of the color images obtained by that of thecontrol couplers C and D and the oxidation product of the same colordeveloping agent as above. The structural formulas of Couplers A and Bof the present invention, as well as control Couplers C and D, are setforth below.

Coupler A Control Coupler C i N=c-NHNoi Cl N\ Control Coupler D DETAILEDDESCRIPTION OF THE INVENTION 0- H3 ll As shown by the spectralabsorption curves of FIGS. 1 and 2, as well as table 1. the couplers Aand B of the present invention have sharper absorption curves, less cyanand yellow components, and better absorption characteristics than thecontrol coupler C or D. That is, as will be understood from table 1, thelonger wave length side value AA L and the shorter wave length sidevalue AA S are smaller in couplers A and B than in either of the controlcouplers C and D. Also, the values of D /DA and D IDA are much smallerin couplers A and B than in the control couplers C and D. As magenta isa color between cyan and yellow, it is required, from the view point ofcolor reproduction for color photography, that the absorption curvethereof be sharp and to have as small as possible proportions ofunnecessary cyan and yellow components The magenta coupler of thepresent invention sufficiently fulfills these requirements and istherefore excellent in comparison with conventional couplers.

In order to demonstrate the fineness of the dye particles in the colorimage obtained, it is useful to employ the value obtained by dividingSelwayns granularity G (see E. W. H. Selwayn; Photographic Journal; 75,571 (1935) and ibid.; 79, l 3 (1939) by the coupling density of sample.

That is, the finer the granularity of the dye, the smaller is the ratioof these values. These ratios are shown for each of the color imagescorresponding to the spectral absorption curves of the accompanyingdrawings in table I.

From table 2, it will be understood that the granularity of the dye ofthe color image obtained from the coupler of the present invention ismuch finer than that obtained from the control coupler C or D. Thus, itis clear that, as the granularity of the dye becomes finer, thetransparency of the dye image is improved, the formation of roughness inthe color image is prevented, and the sharpness of color image isimproved.

Also, each sample having the color image corresponding to the spectralabsorption curve shown in the accompanying drawing was exposed for 50hours to a XF-2O type xenon lamp Fade Tester manufactured by K .K.Shimazu Seisakusho and the fading of the color image was then measured.The results are shown in table 3, which shows that the color imageobtained from the couplers of the present invention had better lightfastness than those obtained from the control couplers.

TABLE 3 Color image Percentage of Fade E 60% F 58% g 79% H 75% Althoughthe mechanism by which the couplers of the present invention provideexcellent, improved color hue, granularity, light fastness, etc., ascompared with the known couplers is not known, it is considered to beprobably mainly due to the fact that the 4-position of the l-phenylnucleus of the coupler has been substituted by the positive methyl groupor methoxy group. However, such excellent coupling results cannot simplybe obtained by replacing only one chlorine atom of the three chlorineatoms on the l-phenyl nucleus as illustrated by those experiments usingcontrol coupler D. That is, control coupler D is similar to coupler B ofthis invention in that the l-phenyl nucleus has two chlorine atoms andone methyoxy group, and the molecular formula and the molecular weightof these two couplers are completely the same. The difference betweenthem is only in the positions of the two chlorine atoms. Thus, the meredifference in the positions of chlorine atoms is seen to produce adecisive change in the photographic properties of the coupler.

The coupler of the present invention can be used not only for naturalcolor photography but also for monochromatic or dichromatic photography.

The couplers of the present invention may generally be preparedaccording to the processes disclosed in British Patent No. 886,723 orBelgian Patent No. 682,384. Examples of preparing the couplers of thisinvention are shown below:

SYNTHESIS EXAMPLE l Preparation of Coupler B a): Preparation ofl-(2,6-dichloro-4-methoxyphenyl)-3-(4-nitrophenoxyacetoamido)-5-pyrazolone.

Into a 1 liter three-necked flask were charged 400 ml. of acetonitrileand 60 g. of l-(2,6-dichloro-4-methoxyphenyl)-3- amino-5-pyrazolone(prepared by the method disclosed in U.S. Pat. No. 3,062,653). Asolution of 56 g. of 4- nitrophenoxy-acetyl chloride in 200 ml. ofacetonitrile was gradually added to the system and the resultant mixturewas refluxed for about 3 hours. After distilling out about 400 ml. ofacetonitrile under a reduced pressure, the reaction mixture was cooledby ice to precipitate crystals, which were collected by filtration andwashed with acetonitrile. and then with methanol to give 75 g. (yieldpercent) of white crystals having a melting point of 2l9220 C. Theanalytical value for nitrogen was 12.50 percent (theoretical value l2.36percent) b): Preparation of l-(2,6-dichloro-4-methoxyphcnyl)- 3-(4-nitroanilino )-5 -pyrazolone.

Into a solution of 21 g. of sodium hydroxide in 60 ml. of water and 240ml. of ethanol was gradually added 79 g. of the product prepared in a)and the resultant mixture was stirred for about 8 hours at roomtemperature. The crystals deposited were filtered off, the filtrate wasmixed with 400 ml. of water, and the mixture was acidified by theaddition of glacial acetic acid. Crystals thus precipitated werecollected by filtration. washed well with water, and then with methanolto give 60 g. (yield 87 percent) of the yellow crystals having a meltingpoint of 28 l-282 C. The product dissolved in ml. dimethylformamide andthe resultant solution was mixed with 800 ml. of methanol to precipitate54 g. of the pure product having a melting point of 283-284 C. with ayield of 78 percent. The analytical value for nitrogen was 14.36(theoretical value 14.18 percent).

SYNTHESIS EXAMPLE 2 l-( 2,6-dichloro-4-methylphenyl )-3- yl hydrazine bydiazotizing and reducing with tin chloride according to-a conventionalmethod. The yield was 62 percent, the melting point thereof was 98l00C., and the analytical value for nitrogen was 14.38 percent (theoreticalvalue 14.66 percent).

By reacting the product prepared above and ethyl-B-imino-B-ethoxypropionate according to a conventional 'method of producing1-aryl-3-amino-5-pyrazolones, the objective pyrazolone having a meltingpoint of 216218 C. was obtained with a yield of 86 percent. Theanalytical value for nitrogenwas 16.03 percent (theoretical value 16.28percent).

b): Preparation of 1-(2,6-dichloro-4-methylphenyl)-3-(4-nitrophenoxyacetamido)-5-pyrazolone.

By following the same procedure as in synthesis example 1 a), using thematerial prepared in a) of this example, the product having a meltingpoint of 233-234 C. was obtained with a yield of 78 percent. Theanalytical value for nitrogen was 12.57 percent (theoretical value 12.81percent).

c): Preparation of l-(2,6-dichloro-4-methylphenyl-3-(4-nitroanilino)-5-pyrazolone. By following the same procedure as insynthesis example 1 b), using the material prepared in b) of thisexample, yellow crystals having a melting point of 266-267 C. wereobtained with a yield of 65 percent. The analytical value for nitrogenwas 14.71 percent (theoretical value 14.77 percent).

SYNTHESIS EXAMPLE 3 Preparation of the Control Coupler D a): Preparationof l-(3,5-dichloro-4-methoxyphenyl)-b 3-(4-phenoxyacetamido)-5-pyrazolone.

By following the procedure of synthesis example 1 a), but usingl-(3,5-dichloro-4-methoxyphenyl)-3-amino-5- pyrazolone having a meltingpoint of 173l 74 C., a product having a melting point of 210 212 C., wasobtained with a yield of 67 percent. The analytical value for nitrogenwas 12.58 percent (theoretical value 12.36 percent).

b): Preparation of l-(3,5-dichloro-4-methoxyphenyl)-3-(4- nitronitroanilino)-5-pyrazolone.

The same procedure as in synthesis example 1 b) was followed, but usingthe material obtained in a) of this example to give yellow-browncrystals having a melting point of 253-254 C. with yield of 74 percent.The analytical value for nitrogen was 3.92 percent (theoretical value14.18 percent).

The present invention will now be explained in more detail by thefollowing illustrative examples.

EXAMPLE 1 A photographic light-sensitive film prepared by applying anordinary green-sensitive silver iodobromide emulsion to a film anddrying was exposed to green light using a stage-type wedge. Afterdeveloping the exposed film in a black and white developer for 3minutes, the film was subjected to reversal exposure with green light,developed for 5 minutes in a magenta developer containing the Coupler Aof the present invention, and washed with water.

The developed film was Subjected to silver bleaching by an ordinaryprocess and fixed in a hypo-containingfixer, whereby a positive magentaimage having excellent transparency was obtained. The spectralabsorption curve of the color image is shown as curve E. in theaccompanying drawing.

The compositions of the black and white developer and the magentadeveloper were as follows;

Black and white developer N-methyl-p-aminophenol Potassium bromide Waterto make 1 Magenta developer Potassium bromide Sodium sulfite Sodiumsulfate Potassium thiocyanate Sodium hydroxide l-(2.6-dichloro-4-methylphenyl)-3-(4- nitroanilino)-$- pyrazolone Hexylene glycol2-methyl-4-N-elhyl-N- methane-sul- 3 g. lOg. 50g.

2g. lOml.

foaminoethylaminoaniline 3/2 sulfate (monohydratc) 2 Water to make IEXAMPLE 2 By following the same procedure as in example 1, but usingcoupler B, (l-(2,6-dichloro-4-methoxyphenyl)-3-(4-nitroanilino)-5-pyrazolone), a-positive magenta image having excellenttransparency was obtained. The spectral absorption curve of the colorimage is Shown as the curve F in the accompanying drawing. I

EXAMPLE 3 By followingthe same procedure as in example 1, but using amagenta developer having the following composition instead of thedeveloper of example l,a positive magenta image having excellenttransparency and A at 545 rn p. was obtained.

EXAMPLE 4 A multilayer reversal color photographic film of a type to bedeveloped in color developers containing couplers was exposed, developedfor 3 minutes in the black and white developer of examplewashed withwater, subjected to reversal exposure with red light, and developed for4 minutes in a cyan developer havingthe following composition.

Cyan Developerv Potassium Bromide 2 3. Potassium thioeyanate. 2 g.Sodium sulfiie 5 g. Sodium hydroxide. 2 g. Z-(Z-propiamido-fi- IphenyIethyD-I- hydroxyanaphthamide 3 g. Hexylene glycol l0 ml.

2-methyI-4-N,N-

diethylaminoaniline hydrochloride 1.5 g. MonobenzyLpaminophenol 0.4 g.Methanol 5 ml.

Water to make I l.

The developed film was washed with water, exposed to blue light, andthen developed for 4 minutes in a yellow developer having the followingcomposition;

Yellow developer Potassium bromide 2 g. Sodium sulfite g. Sodiumhydroxide 2 g Benzoylacetanilide 1.5 g. 4-N,N-diethylaminoanilinesulfate 2 g.

Water to make I 1.

After washing with water, the film was then developed for 2 minutes inthe black and white developer described above and washed with water.Thereafter, the film was exposed to white light and developed for 4minutes in a magenta developer having the following composition;

Magenta developer Potassium bromide 2 g. Sodium sulfite 5 g. Sodiumhydroxide 2 g.

l-(2.6-dichloro-4- methoxyphenyl)-3-(4- nitroanilinO)-5- pyrazolone liSg. l-methyl-4-N.N-

diethylaminoaniline hydrochloride 1.5 g.

Water to make I L After washing with water, the film was subjected tosilver bleaching by an ordinary process and fixed in a hypo-containingfixer to give a color photographic image having excellent transparency.

What is claimed is:

1. A silver halide color photographic developing process which comprisescolor developing an exposed silver halide image using a solutioncontaining an aromatic primary amino developing agent and couple of theformula wherein R is a member selected from the group consisting of amethyl group and a methoxy group.

5. The color photographic developer of claim 4 wherein said compound isl-(2,6-dichloro-4-methylphenyl)-3-(4- nitroanilino)-5-pyrazolone.

6. The color photographic developer of claim 4 wherein said compound isl-(2,6-dichloro-4-methoxy-phenyl)-3-(4- nitro-anilino)-5-pyrazolone.

2. The color photographic developing process of claim 1 wherein saidcoupler is1-(2,6-dichloro-4-methylphenyl)-3-(4-nitroanilino)-5-pyrazolone.
 3. Thecolor photographic developing process of claim 1 wherein said coupler is1-(2,6-dichloro-4-methoxy-phenyl)-3-(4-nitro-anilino)-5-pyrazolone.
 4. Acolor photographic developer comprising an aromatic amino developingagent and a compound of the formula wherein R is a member selected fromthe group consisting of a methyl group and a methoxy group.
 5. The colorphotographic developer of claim 4 wherein said compound is1-(2,6-dichloro-4-methylphenyl)-3-(4-nitroanilino)-5-pyrazolone.
 6. Thecolor photographic developer of claim 4 wherein said compound is1-(2,6-dichloro-4-methoxy-phenyl)-3-(4-nitro-anilino)-5-pyrazolone.